1. Field of the Invention
The present invention relates in general to the field of information handling system power subsystems, and more particularly to a system and method for dynamic modular information handling system power distribution.
2. Description of the Related Art
As the value and use of information continues to increase, individuals and businesses seek additional ways to process and store information. One option available to users is information handling systems. An information handling system generally processes, compiles, stores, and/or communicates information or data for business, personal, or other purposes thereby allowing users to take advantage of the value of the information. Because technology and information handling needs and requirements vary between different users or applications, information handling systems may also vary regarding what information is handled, how the information is handled, how much information is processed, stored, or communicated, and how quickly and efficiently the information may be processed, stored, or communicated. The variations in information handling systems allow for information handling systems to be general or configured for a specific user or specific use such as financial transaction processing, airline reservations, enterprise data storage, or global communications. In addition, information handling systems may include a variety of hardware and software components that may be configured to process, store, and communicate information and may include one or more computer systems, data storage systems, and networking systems.
In order to operate properly, information handling systems typically need a reliable power source to power electronic components and cooling to remove excess heat produced as a byproduct of power applied to the electronic components. In most operating conditions, if an information handling system continues to run without adequate cooling, the electronic components will overheat and destroy themselves. To prevent overheating, information handling systems typically include internal temperature gauges to measure operating temperatures and a feedback to the cooling system so that cooling fans operate with enough speed to remove excess heat. Under conditions of high thermal stress, the electronic components are sometimes “throttled” to run at reduced clock speeds so that the amount of heat produced by the electronic components is reduced. One trend that has developed in the server information handling system field is the support of multiple information handling systems in a common chassis having common power and cooling subsystems. A chassis management controller (CMC) distributes power and cooling resources between the multiple information handling systems supported by the chassis. Baseboard management controllers (BMC) running on each information handling system cooperate with the chassis management controller to enforce power and cooling constraints that ensure proper operation of the chassis as a whole.
One of the difficulties with chassis-supported modular information handling systems is that a wide range of power and cooling demands may exist during the course of normal operations. For example, the power consumed by a central processing unit (CPU) varies substantially depending on the workload of the CPU. A CMC power manager has to ensure that adequate power is available to run each information handling system supported by the chassis over the range of operations allowed for each information handling system. If, for instance, the total power that the information handling systems can demand exceeds the power available from the power supply, the CMC power manager typically restricts the operation of one or more information handling system modules to ensure that total power demand will not exceed available power. To enforce power consumption limitations, the CMC power manager provides a maximum power consumption allotment to each BMC so that the BMC can prevent its information handling system from drawing greater than the allotted power. In addition to allotting power to the information handling system modules, the CMC power manager also must ensure that adequate power is available to run cooling fans that cool the modules. Typically, enough power is reserved so that the cooling fans can operate at full speed. One safety measure calls for the fans to automatically operate at full speed in the event that the CMC fails. In such a situation, adequate power should remain available to operate the information handling system modules at the maximum power allotment stored in each BMC, however, the power allotment to the fans reduces the amount of power available to the information handling system modules during normal operations.